In testing network devices it is desirable to execute tests that utilize clocks that are offset in phase and/or frequency with respect to each other. For example, in one test, it may be desirable to test an IEEE 1588 compliant device's response to different master clock sources. In order to perform such a test, IEEE 1588 masters with different clocks must be emulated. One way to emulate devices with different clocks is to use individual clock hardware in each device to generate its own clock values. However, this approach does not allow for simulation of clock jitter, latency, or other effects related to changes in clock frequency and/or phase over time. In addition, a solution that requires dedicated clock hardware for each clock is not scalable.
FIG. 1 illustrates a generic test setup for testing a device under test. Referring to FIG. 1, network equipment test device 100 transmits test packets to a device under test 102. More particularly, a network interface card 104 on network equipment test device 100 transmits a test packet to device under test 102, and device under test 102 returns the test packet to another network interface card 108 on network equipment test device 100. In a timing related test, test packet 106 may have a timestamp value that is generated based on a clock local to network equipment test device 100. If a stream of test packets 106 is transmitted to device under test 102, it may be desirable to simulate clock drift or other phenomena to see how device under test 102 responds to such changes in clock frequency and/or phase.
Accordingly, there exists a need for methods, systems, and computer readable media for your emulating network devices with different clocks.